Friday 14 September 2012 14.39 EDT
First published on Friday 14 September 2012 14.39 EDT

While across the Middle East and wider Muslim world Friday was a day of demonstrations, burning and violence, in Benghazi tears were shed. They came from Yousef al-Magariaf, president of Libya's new parliament, as he described the death of US ambassador Chris Stevens and three of his colleagues.

"Definitely, it was a deliberate attack," said al-Magariaf as the city braced for further protests over the crude video, the Innocence of Muslims. He insisted it was an assassination, and not a riot gone wrong.

"It was a prepared attack in every sense of the word. I was given details of this by witnesses and this makes me 100% sure that this was pre-planned to hit at the core of the relationship between Libya and the United States."

While events in Libya were relatively peaceful, that was not true for other cities that saw violent clashes – among them Khartoum, the Sudanese capital, where the German embassy was burned and the British embassy attacked. Last night, US Marine were reportedly on their way to Sudan.

By Friday morning what had begun as a small protest outside the US embassy in Cairo on Tuesday had set off protests across the Muslim world. In Srinagar, Kashmir, lawyers protesting against the film held placards carrying the slogan: "America your death has come."

As protesters gathered after Friday prayers in Tunis, Khartoum, Cairo and Sana'a, capital of Yemen, some were encouraged by official interventions.

In the Tunisian capital, where the Arab spring began a year ago, members of the country's interim parliament condemned the film before the planned protests.

The Tunis demonstration began in quiet good spirits but ended in violence, as demonstrators breached the US embassy compound walls, lit fires and tore down the US flag, replacing it with a black Salafist banner. Elsewhere in the city, the American school was attacked.

There were also protests reported in Indonesia, Iraq, Iran, Lebanon and Bahrain. The numbers involved were small in comparison to the vast demonstrations of the Arab spring.

By the end of the day, the back of the Tunis embassy compound was billowing flames and black smoke, while Tunisian riot police, visible inside the compound, appeared to have succeeded in protecting the main embassy building. Later, however, two protesters were reportedly killed and 40 injured during the attempt to storm it.

It emerged that Libya had temporarily closed its airspace over Benghazi airport because of heavy anti-aircraft fire by Islamists aiming at US reconnaissance drones over the city, after Barack Obama vowed to bring the ambassador's killers to justice.

The closure of the airport prompted speculation that the US was deploying special forces in preparation for a raid against the militants involved in the attack.

In Khartoum – where some of the worst violence took place – there were suggestions of direct involvement by the government in encouraging the protests. Richard Woods, headmaster of a Khartoum high school, emailed the Guardian to say transportation appeared to have been provided for demonstrators, including official buses, according to another witness.

"It appears that after prayers, buses and trucks were on hand to transport people," said Woods.

"We have just had afternoon prayers and again you can see people being picked up by trucks and buses around the mosques."

In Cairo there was violence throughout the day around Tahrir Square and one protester died after clashes with police near the US embassy. But others there who had been angry about the film earlier in the week were not prepared to participate.

Among these was Wesam Abdel-Wareth, who organised Tuesday's protest, and said he would not protest on Friday.

"Our demands have been met," he said. The demands included statements by the Coptic Church distancing itself from the film, an apology by the US embassy in Cairo cancelling an alleged screening of the film.

He added that he understood that the US administration is not responsible for the film and praised secretary of state Hillary Clinton for condemning it.

The search engine Google on Friday night rejected a request by the Obama administration to reconsider a decision to keep a clip from Innocence of Muslims online, Reuters reported.